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This study investigated climate-induced shifts in irrigation water demand and supply of the major staple and water-intensive crops (wheat and rice) in the Indus, Ganges and Brahmaputra (IGB) river basins of South Asia. It explores irrigation water usage during climate-sensitive crop growth phases (i.e., vegetative and reproductive which required ~ 60% of the total crop water demand), which is supposed to be crucial for long-term integrated crop water management. A hydrology vegetation model LPJmL is forced with an ensemble of eight downscaled (5 arc-min) GCM’s using a mix of two emission scenarios i.e., RCP4.5-SSP1 and RCP8.5-SSP3. To investigate phase-specific shifts in crop water use during the period 1981-2100, trend analysis is performed. It shows a significant (p

In this modern era due to multidimensional problems associated with petrochemical fuels, the scientific community is showing a burgeoning interest in microalgae due to their potential applications which are indispensable for economic amelioration. Microalgae are a fundamental source of oils and various other biomolecules that can be used in the production of biofuels and various other value-added bioproducts. However, implication of microalgae-based biofuels is not economically viable due to various factors. One of these prime reasons is the cost associated with its harvesting. This review focuses on various harvesting techniques applied to microalgae in the last 2/3 decades, presenting the main benefits and drawbacks of each method to allow the selection of appropriate method(s) for economically harvesting microalgal biomass. According to this review, use of any single technique is not viable for harvesting microalgal biomass. However, keeping in view the morphological characteristics of the microalgae, growth density, utility purpose of the harvested biomass, harvesting scale and physico-chemical characteristics of the production medium, these techniques should be applied in suitable combinations to obtain fruitful results.

Pomegranate peels (PPW) as municipal waste is inexpensive biomass that could be a renewable source of sugars particularly rich in hemicellulosic contents. The subsequent conversion of available sugars in PPW can provide prospective strategy for cost-effective bioenergy production. In this study, an experimental setup based on CCD was implemented with the aim of bioconversion of biomass into bioethanol. The factors considered were Hydrochloric acid concentration (X1), the hydrolysis temperature (X2) and time (X3) for optimization with dilute Hydrochloric acid (HCl) saccharification. The present study investigates the optimised level of bioethanol synthesis from acid pre-treated PPW explained by RSM. Subsequently, three yeasts viz. Saccharomyces cerevisiae K7, Metschnikowia sp. Y31 and M. cibodasensis Y34 were utilized for fermentation of acid hydrolysed and detoxified feed stocks. Optimum values of reducing sugars 48.02 ± 0.02 (gL−1) and total carbohydrates 205.88 ± 0.13 (gL−1) were found when PPW was hydrolyzed with 1% HCl concentration at 100˚C of temperature for 30 min. Later on, fermentation of PPWH after detoxification with 2.5% activated charcoal. The significant ethanol (g ethanol/g of reducing sugars) yields after fermentation with Metschnikowia sp. Y31 and M. cibodasensis Y34 found to be 0.40 ± 0.03 on day 5 and 0.41 ± 0.02 on last day of experiment correspondingly. Saccharomyces cerevisiae K7 also produce maximum ethanol 0.40 ± 0.00 on last day of incubation utilizing the PPWH. The bioconversion of commonly available PPW into bioethanol as emphasize in this study could be a hopeful expectation and also cost-effective to meet today energy crisis.

Agro-industrial wastes can be processed into valuable products. Successively, current investigation is an effort to optimize the acid hydrolysis of pomegranate peels waste (PPW) using central composite design (CCD) of response surface methodology (RSM) for ethanol production. Concentration of sulfuric acid, temperature, and time of hydrolysis were used as dependent variables, whereas reducing sugars, total carbohydrates, extractives, weight loss, hemicellulose, cellulose, and lignin contents were recorded as responses for PPW decomposition. The highest glucose level of 0.56 ± 0.04 mg mL−1 (with 5% acid concentration at 100 °C for 30 min) and carbohydrate contents of 1.53 ± 0.07 mg mL−1 (with 3% acid concentration at 75 °C for 45 min) were obtained. Subsequently, detoxification of hydrolysate was conducted employing 2.5% activated charcoal that reduced 62% of phenolic compounds. Detoxified hydrolysate was subjected to fermentation by ethanologenic yeasts: Metschnikowia sp. Y31, Metschnikowia cibodasensis Y34, and Saccharomyces cerevisiae K7 for 10 days experiment. Significant ethanol yield of 0.42 ± 0.08 g g−1 was noticed by Metschnikowia sp. Y31 on day 5 and 0.41 ± 0.07 g g−1 for Metschnikowia cibodasensis Y34 on day 2. The results demonstrated the hopeful prospect for bioethanologenesis using cellulosic wastes at marketable level.

In the present study, the mixotrophic growth of the microalga Nannochloropsis sp. BR2 in sugarcane bagasse was analyzed and compared with its photoautotrophic cultivation. Nannochloropsis cultures cultivated mixotrophically in sugarcane bagasse showed significantly higher biomass productivity, fatty acid methyl ester (FAME) and protein contents of 63.28 mg L−1 d−1, 170.51 mg g−1 and 35.2% of dry weight, respectively, compared to the photoautotrophic cultivations with biomass productivity, FAME and protein contents of 51 mg L−1 d−1, 139.21 mg g−1 and 31.6% of dry weight. Whereas, total carotenoid during photoautotrophic cultivation was 5.833 mg g−1 and decreased to 4.542 mg g−1 in mixotrophic cultures. This can be explained by the additional carbon source in the form of sugars that are metabolized to the fatty acid building block acetyl-CoA, while photosynthetic pigments were less needed. Findings of this study demonstrate that acid-pretreated hydrolysate of lignocellulosic waste from sugarcane bagasse can be developed into a potential feedstock for efficient microalgal cultivation.

Today, global focus of research is to explore the solution of energy crisis and environmental pollution. Like other agricultural countries, bulk quantities of watermelon peels (WMP) are disposed-off in environment as waste in Pakistan and appropriate management of this waste is the need of hour to save environment from pollution. The work emphasizes the role of ethanologenic yeasts to utilize significant sugars present in WMP for low-cost bioethanol fermentation. Dilute hydrochloric acid hydrolysis of WMP was carried out on optimized conditions employing RSM (response surface methodology) following central composite design (CCD). This experimental design is based on optimization of ethanologenesis involving some key independent parameters such as WMP hydrolysate and synthetic media ratio (X1), incubation temperature (X2) and incubation temperature (X3) for maximal ethanol yield exploiting standard (Saccharomyces cerevisiae K7) as well as experimental (Metchnikowia cibodasensisY34) yeasts. The results revealed that maximal ethanol yields obtained from S. cerevisiae K7 was 0.36±0.02 g/g of reducing sugars whereas M. cibodasensisY34, yielded 0.40±0.01 g ethanol/g of reducing sugars. The yeast isolate M. cibodasensisY34 appeared as promising ethanologen and embodies prospective potential for fermentative valorization of WMP-to-bioethanol. Resumo Hoje, o foco global da pesquisa é explorar a solução da crise energética e da poluição ambiental. Como em outros países agrícolas, grandes quantidades de cascas de melancia (WMP) são descartadas como resíduos no meio ambiente no Paquistão, mas a gestão adequada desses resíduos é a mais recente solução para salvar o meio ambiente da poluição. O trabalho enfatiza o papel das leveduras etanologênicas para utilizar açúcares significativos presentes no WMP para fermentação de bioetanol de baixo custo. A hidrólise de ácido clorídrico diluído de WMP foi realizada em condições otimizadas empregando RSM (metodologia de superfície de resposta) e seguindo o projeto de composto central (CCD). Este projeto experimental é baseado na otimização da etanologenesis envolvendo alguns parâmetros independentes importantes, como hidrolisado de WMP e razão de meio sintético (X1), temperatura de incubação (X2) e temperatura de incubação (X3) para rendimento máximo de etanol explorando o padrão (Saccharomyces cerevisiae K7) também como leveduras experimentais (Metchnikowia cibodasensis Y34). Os resultados revelaram que os rendimentos máximos de etanol obtidos a partir de S. cerevisiae K7 foi de 0,36 ± 0,02 g / g de açúcares redutores, enquanto M. cibodasensis Y34 rendeu 0,40 ± 0,01 g de etanol / g de açúcares redutores. O isolado de levedura M. cibodasensis Y34 apareceu como um etanologeno promissor e incorpora um potencial prospectivo para a valorização fermentativa de WMP em bioetanol.

Accurate (spatio-temporal) estimation of the crop yield relation to climate variables is essential in the densely populated Indus, Ganges, and Brahmaputra (IGB) river basins of South Asia for devising appropriate adaptation strategies to ensure regional food and water security. This study examines wheat (Triticum aestivum) and rice (Oryza sativa) crop yields&rsquo, sensitivity to primary climate variables (i.e., temperature and precipitation) and related changes in irrigation water demand at different spatial (i.e., province/state, districts and grid cell) and temporal (i.e., seasonal and crop growth phase) scales. To estimate the climate driven variations in crop yields, observed and modelled data applying the Lund-Potsdam-Jena managed Land (LPJmL) model are used for six selected study sites in the IGB river basins over the period 1981&ndash, 2010. Our statistical analysis underscores the importance of impacts assessments at higher spatio-temporal scales. Our grid cell (aggregated over study sites) scale analysis shows that 27&ndash, 72% variations in wheat and 17&ndash, 55% in rice crop yields are linked with temperature variations at a significance level of p &lt, 0.001. In the absence of irrigation application, up to 39% variations in wheat and up to 75% variations in rice crop yields are associated with precipitation changes in all study sites. Whereas, observed crop yields show weak correlations with temperature at a coarser resolution, i.e., up to 4% at province and up to 31% at district scales. Crop yields also showed stronger sensitivity to climate variables at higher temporal scale (i.e., vegetative and reproductive phases) having statistically strong negative relationship with temperature and positive with precipitation during the reproductive phase. Similarly, crop phase-specific variations in climate variables have considerable impacts (i.e., quantity and timing) on irrigation water demand. For improved crop water planning, we suggest integrated climate impact assessments at higher spatio-temporal scales which can help to devise appropriate adaptation strategies for sustaining future food demand.

Changing irrigation water demand (IWD) and supply (IWS) patterns (size and time) under increased climate variability and socio-economic development is significantly effecting the water and food pro...

Climate change has become a global phenomenon having severe ramifications on socio-economic sectors such as agriculture, water resources, environment and health. The effects of changing climate are much more prominent on developing economies as compared to the implications on well-developed industrial powers. Pakistan is one of the struggling agricultural economies confronting the issues of food insecurity as a consequence of profound climatic conditions. Notable changes in climatic factors such as temperature can have a direct effect on Growing Degree Days (GDD) and may alter the growing season length (GSL). Growing season length is an important factor in ensuring that each crop developmental stage has a sufficient period for the transition to the next developmental stage. Lengthening or shortening of GSL can have dire threats to crop development and ultimately, production. This study has been conducted to assess the changes in GSL in response to the variability in daily maximum and minimum temperatures with a base temperature of 5°C across Northern, Central and Southern Pakistan. RCP 4.5 and 8.5 have shown an increase of 2°C and 5.4°C in minimum and maximum temperatures, respectively.

Overuse of the fossil fuels to fulfill existing energy requirements has generated various environmental problems like global warming. Emergence of environmental issues due to burning of the fossil fuel resources has provoked researchers to explore alternative sources of fuel. In this scenario, microalgal biofuels could present a promising alternative fuel if produced cost-effectively without competing for freshwater resources and arable land. Aim of the present study was to grow microalgae by employing lignocellulosic waste for production of lipids. Scenedesmus dimorphus NT8c was chosen based on its ability to tolerate heat, rapid growth, and ease of harvesting by overnight settling. Biochemical composition and growth parameters of microalgae were analyzed when cultivated mixotrophically on sugarcane bagasse hydrolysate, a low-value agricultural by-product, that is, currently underutilized. Despite a slight increase in turbidity in the medium, S. dimorphus NT8c cultures raised mixotrophically in 5 g/L sugarcane bagasse hydrolysate displayed significantly higher growth rates compared to photoautotrophic cultivation with an overall biomass productivity of 119.5 mg L d, protein contents of 34.82% and fatty acid contents of 15.41%. Thus, microalgae cultivated mixotrophically are capable of photosynthesizing while metabolizing and assimilating organic carbon, significant increases of biomass and lipid productivity can be achieved. However, high supplementation with organic carbon can result in unfavorable levels of turbidity and bacterial growth, reducing microalgal biomass productivity.

Phenotypic characteristics while complimenting 16S rRNA gene sequencing in identifying bacteria become decisive in solving conflicts of equal % similarity of a given DNA sequence to more than one classified microorganisms. "Phenotypic light" may also indicate right direction when a new species' 16S rDNA sequence is under consideration. In fact 16S rRNA gene sequences give indication that either a novel species has been isolated or the test organism is identified. In each case additional tests are required for resolving different issues. Predictions of microbial phenotypes from metagenomic data depend heavily on our knowledge of expressed genes. Thus renaissance of microbial phenotypic characterization is likely to emerge at par with genotypic signatures. Interplay of these and other complimentary levels of analyses are likely to lead DNA barcoding for microorganisms as it has provided efficient methods for species-level identifications of animals and plants. In this review, an attempt has been made to realize the reader(s) importance of interplay of genotypic and phenotypic characteristics of bacteria for development of comprehensive and more stable classification schemes. It is expected that future valid classification schemes will be based on the phenetic relationships of microorganisms.

Additional file 1: Figure S1. Desirability profile for predicted values of Ctec and Htec Novozymes for sugarcane bagasse hydrolysis.

Climatic vicissitudes have laid further stress on already dwindling fossil fuels. In response to the emerging energy needs, biofuels can be considered as the safest and sustainable energy resources. At present, ethanol fermentations have been successful in fueling motor vehicles in some countries. However, with the existing population dynamic, obtaining ethanol from food competing resources/commodities might not be a desirable option. Therefore, non-food competing second-generation biofuels are the right choice to accommodate the increasing energy demand. Regarding the production of biohydrogen, shifting from food competing substrates to non-food competing natural resources would be geared at dawn of biohydrogen productions. In this review potential of lignocellulosic biomass, the largest renewable natural resource for biofuels’ generation has been discussed in reference to economical consideration. The strategies will likely involve thermophilic microbes possessing cellulolytic as well as ethanologenic potential. The process economics might be supported to some extent by procuring byproducts of some value from the bioenergy fermentations. Nutritional evaluation of the fermentation residues for animal feed may improve the biofuel economics. The proposed strategies appear promising more specifically in reference to climatic conditions of Pakistan.